This question relates to food webs and food chains. In most cases removing one of the organisms in a food web adversely effects all of the others in that particular environment. The local ecosystem is usually finely balanced. for example the removal of a predator like a fox would increase the rabbit population, which would lessen the rabbits food supply due to overpopulation, that would eventually lead to a dramatic fall in rabbit population due to a self created fammine. Also if the fox had a predator such as a bear then their numbers would fall due to their food source being removed from their ecosystem. So it is like a domino effect with the absence of one organism leading to the downfall of others. the whole dynamic of the local food web would change to with other organisms moving in to capitalise on the now less competetive ecosystem.

Actually this is a matter of very serious concern. There has been a huge explosion worldwide of jellyfish, in particular, venemous jellyfish such as the small but deadly Box jellyfish and the tiny, almost invisible Irukandji jellyfish. Stings from these require hospitalisation and may prove fatal. The increase is due to global warming and overfishing.http://www.telegraph.co.uk/earth/earthnews/3324659/Killer-jellyfish-population-explosion-warning.html

I live in an area dominated by Chinese and Vietnamese groceries, so I get to try many exotic foods. The dried jellyfish, however, I haven''t gotten to yet. We may all have to learn.

In general, overuse leads to the increase of dangerous and 'weed'species worldwide in a range of environments.

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